1. Field of the Invention
The present invention relates to the use of elastomer encased active ingredients in chewable articles of commerce for the purposes of providing a long term release of such active ingredients during the mastication of such articles of commerce.
2. Description of the Prior Art
Various types of chewable articles of commerce are known. They would include those of a comestible or semi-comestible type and those of a mechanical type.
Various types of active agents or ingredients are used in various of these chewable articles of commerce, particularly the comestible or semi-comestible types thereof. Such active ingredients would include flavorants, intense sweeteners, colorants, medicaments and effervescent agents (CO.sub.2 or other gas generating systems).
For commercial acceptance purposes, it is often desirable to provide for extended periods of release of such active ingredients from the chewable articles of commerce in which they are used, during the mastication of such products. A technique commonly employed in this regard, is the encapsulation of the active ingredient within a shell of a material designed to provide a complete coating around particles of the active ingredient. Such encapsulation procedures usually require the use of solutions or dispersions of the coating material, and the use of spray drying or drum drying procedures for the application of the coating material to the particles of the active ingredient and/or for the removal of the solvent values from the coated particles.
Such procedures, however, are basically limited to being useful only with those types of coating materials which are readily soluble in one or more solvents and/or those coating systems which can be readily dried without subjecting the active ingredient to any adverse heat or solvation history. Such prior art systems are, for the most part, not useful with elastomers. Further, such prior art encapsulation systems tend to be limited in terms of the length of time that they can delay or extend the release of the active ingredients, i.e., usually only over a period of up to about five to ten minutes, at most. Further, in many cases, where the active ingredient is released from such encapsulating agents it may only be released in a single burst of the active ingredient. Also, each of the prior art means available for encapsulating active ingredients tend to be limited, respectively, in terms of the active ingredients with which they can be used and/or with respect to the chewable products in which they can be employed.
U.K. No. 2,166,651 discloses the use of porous controled release powders having an average particle size in the range of 0.1 to 125 .mu.m (microns) which comprise various types of active ingredients in a matrix of non-toxic polymers. The active ingredients are released from the powders by dissolution. The particle sizes are designed to be unaffected by chewing action even though the powders may be used in chewable products.
Prior to the present invention, therefore, it has not been readily possible, if at all, to provide a single non-porous, chewable, carrier means for incorporating a wide variety of active ingredient in a wide variety of the various types of chewable products commercially available, in such a way as to provide for relatively long periods of release of the active ingredient from such products.